Sub-line Differences among C57 Black Mice in Response to Trypan Blue and Outcross

Abstract

THERE exist many sub-lines of the highly inbred C57 Black strain of mice. One of the characteristics of the C57 Blacks, especially noted in sub-lines six and ten, has been the occurrence of sporadic eye defects^1–3, attributed to non-hereditary variability in a genetically determined threshold for abnormality¹. The anophthalmic pheno-type of the mouse has been extensively examined by Chase^1,4 and, more recently in the ZRDCT–An line, by Beck^3,5,6. It is characterized by complete bilateral eyeless-ness among 90 per cent of the individuals homozygous for the recessive oligogene (ey) and most of the polygenic modifiers, and severe microphthalmia in the remaining 10 per cent.